[11] HOW DOES THE SDF MAIL SERVER WORK? IS IT RELIABLE? HOW?

     INTERNET Electronic Mail on SDF is handled by the 'sendmail' daemon
     configured to answer up to 128 requests at a time.  'sendmail' implements
     the TCP/IP SMTP (Simple Mail Transfer Protocol).  The server is at any
     given time working on 25-50 incoming/outgoing pieces of mail with a queue
     of just under 200 messages (as of 31-Mar-06).

     IS IT RELIABLE?

     Yes, it is reliable.  However, it is not recommended for emergencies.
     If you are dying, please call 911.  Do not use email.  Likewise, if
     you need to communicate something quickly, please call the recipient.

     IF THE MAIL SERVER IS DOWN, WHERE DOES MY MAIL GO? DO I LOSE IT?

     Absolutely not.  All SMTP mail servers should be configured to retry
     to send email to a recipient SMTP server at a set interval for,
     at the very least, 5 days before returning to sender.

     SDF is configured to retry to send pending your outgoing messages every
     30 minutes for 5 days before returning them to you.
  
     Again, no properly configured sending server is going to dump your
     email just because the server didn't respond the first time, or the
     second time or even the 30th time.  It will take a server being down
     the good portion of a week for mail to be 'bounced' back to the sender.
     You may assume that it works otherwise, but that just is not the truth. 
     
     SDF also has secondary MXes (Mail eXchangers) which can accept SDF
     email during the very rare occassions that the primary MX is down
     for maintenance or otherwise.  This email is then queued via UUCP
     (UNIX to UNIX CoPy) and is polled by the mail server every 60 minutes.

     DOES SDF FILTER EMAIL BY CONTENT?
 
     ABSOLUTELY NOT!  Your email is yours.  We honestly have no time and no
     desire to scan email content.  Regardless, we find the idea of content
     scanning highly unethical.

     DO YOU BLOCK OR WHITELIST ANY SMTP SENDING SERVERS?

     SDF, like other organizations, uses the Open Relay Database ordb.org.
     The ORDB is a very reliable method of preventing reception from rogue
     SPAM senders.  It essentially denies reception for email from hosts
     that are either purposely or accidentally configured to allow anyone
     to send email to anyone through them.  It also tracks senders that do 
     not have a PTR record (a DNS reverse look up pointer).  

     You possibly will still receive spam as it is an unfortunately 
     inevitability with internet email these days.   The best words of
     advice is to not use your email address on the WWW, or if you must,
     obscure it in such a way that only a human could figure it out.

     We also feel that if you want to filter your own email, then it is up
     to you.  You also deserve to receive every email directed towards you
     and we should not, in any way, censor or filter email destined to you
     with exception of the highly regarded ORDB project.

     We recommend that any filtering you do be done offsite.  Most client
     email programs such as Mail.APP (MACOS X) will do a sufficient job at
     filtering 'junk' for you.  While procmail could be used for the same 
     purpose, it is highly more advantagous for you to not use SDF's CPU but
     rather just download all of your email and filter it on your machine.
